Many milkfish fish consumed by society, but there are some people who are less fond of fish due to the large number of milkfish spines present on the fish whitefish. One of the alternatives offered, namely in the form of milkfish fillets. The purpose of this research is to know the best results on the treatment of Chitosan concentration and long storage on a storage temperature of refrigerator to the quality of physical, chemical and organoleptik fish fillet banding. The study use a factorial completely randomized Design with two-factor and 2 replications. The first Factor concentration of Chitosan (b/v), consisting of: C1 = C2 = 0%, 1%, 2% and C3 = C4 = 3% and the second Factor prolonged storage consisting of: P1 = P2 = 0 days, 4 days, 8 days = P3 and P4 = 12 days. Based on the results of the chemical analysis, microbiology and organoleptic obtained the best concentration of Chitosan treatment combination 2% can prolong the save milkfish fillet on the temperature of the refrigerator for storage 8 days produce milkfish fillet with criteria water content 76,2250%, water activity 0.85% pH 5.86, , total microbial 4,6845 log CFU/g of the test shows negative Postma, (-) (milkfish fillet has not experienced canker). The average results of organoleptic scooring showed the highest value of the texture of 2.90 (somewhat hard), the scent of 3.30 (acid) and color of 2.95 (white is rather dull, there is very little streaks).